But I can't for the life of me find an example that does this (substitutions within substitutions).

When doing substitutions like this, /e is your friend.   $text =~ s/\#\w+\#/$hash{$1}/eg; /e forces the right-hand side of the s/// to be evaluated as a Perl expression, and the result substituted for whatever the left-hand side matched. The boundary between interpolation and substitution can seem pretty hazy, but it makes a bit more sense if you imagine that the regexp is "compiled" immediately before it is executed. At that point, $1 either doesn't have a value, or holds a value from a prior regexp. Neither is what you want.

Consult perlre for full details.

In reply to Re: regex substitution by dws
in thread regex substitution by michellem

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